Stem-cell therapy facing FDA pressure

April 20, 2010|By Jason Blevins, The Denver Post

To 62-year-old Hal Kaye, the injection of his own stem cells into his battered ankle was a miracle cure that saved him from debilitating surgery.

To the Food and Drug Administration, the treatment pioneered by a doctor in the Denver suburb of Broomfield appears to be a misuse of a drug that requires licensing and federal scrutiny before it's used on patients.

And that puts Dr. Chris Centeno on the front line of a simmering dispute over the use and regulation of adult stem cells, which can be cast as either a rogue therapy or breakthrough panacea.

Centeno says his procedure -- Regenexx -- is one of the first in the United States to bridge the gap between stem-cell research and actual treatment. Regenexx involves harvesting a patient's cells from bone marrow, growing more in a lab, then injecting the tissue-repairing cells into damaged joints or even lumbar discs.

Kaye is one of 500 patients who, since 2006, have paid several thousand dollars for a chance to regain their youthful bounce with Centeno's stem-cell therapy. In Kaye's case, the treatment ended years of pain that five orthopedists said could be fixed only by fusing his ankle.

Today, three years after his stem-cell treatment, Kaye says he plays golf "whenever it's sunny."

"I can walk anywhere now," said Kaye, who hasn't used a cane since his Regenexx treatment. "It's been an incredible recovery."

But the FDA says stem cells are really a type of drug that requires intensive study and licensing. The agency sent Centeno a letter in 2008 warning him that lack of FDA licensing for Regenexx appeared to be in violation of the Public Health Service Act. The FDA asked Centeno to write a letter detailing "steps you have taken or will take to address the violations."

Centeno, 46, sent a response to the FDA but said he has yet to receive a formal reply. Centeno asserts that a person's own stem cells, which he multiplies in a culture of the patient's own blood in a controlled lab, are not a drug.

While Centeno circumvents the FDA, at least one other company is working with the agency to treat adults with their own stem cells.

In Louisiana, the 4-year-old TCA Cellular Therapy company has several ongoing FDA-approved clinical trials on humans, using patients' own stem cells to treat heart and vascular diseases. The company is waiting for FDA review of its plan for clinical trials using stem cells to treat spinal cord injuries and Amyotrophic Lateral Sclerosis, or ALS, known as Lou Gehrig's disease.

Centeno insists that the FDA exceeded its authority when, in an effort to prevent the spread of disease, it decided in 2005 that a patient's own stem cells should be regulated as if they were being used on another human.

But the medical community largely has supported the change.

An October 2006 report in the New England Journal of Medicine analyzed the FDA's updated regulation of stem cell-based therapies. The report said researchers should be able to prove stem cells won't transmit disease and will be pure, effective and safe. The authors concluded existing regulations governing stem cells "provide an appropriate structure for ensuring the safety and efficacy of the next generation of stem cell-based products."

The International Cellular Medicine Society, which Centeno helped establish to set professional guidelines for adult stem-cell therapies and now counts 300 physicians in its ranks, is meeting this month with the FDA to discuss the issue of whether a patient's own cells classify as a regulated drug.

A hard-line stance by the FDA could force Centeno to go abroad with his Regenexx procedure, which he licenses to other doctors. He is already helping to open a Regenexx clinic in an orthopedic hospital in China that specializes in medical tourism and caters to patients seeking unconventional medical treatment.

Harvesting, cultivating and three injections of stem cells at Centeno's clinic costs $8,000 and is not covered by most insurance policies.

Centeno's treatment -- three 10-minute injections -- can flood an area with as many as 40 million stem cells. By comparison, microfracture, a surgical technique that involves creating tiny breaks in a bone, bathes an injured joint in a few hundred thousand stem cells.

"The body sometimes has a hard time getting enough stem cells to an area, and what we do is simply amplify the number of cells," Centeno said.

Paul Pendleton is certain that adult stem-cell therapy could someday end joint-replacement surgery. He says it already saved him from replacing his knee. He was about to give up decades of weightlifting and regular workouts when he found Centeno a year ago.

"It feels like my knee did 20 years ago. I'm back doing lunges, teaching my spinning classes," said the 53-year-old petroleum engineer. "The knee seems kind of bulletproof to me. It was a solution that conventional medicine could not offer."